Experimental Signatures of Burn Propagation and Robust Ignition in Laser Indirect Drive Implosions on the National Ignition Facility

ORAL  · Invited

Abstract

An important aspect of central hot-spot ignition implosion designs is observing that the central ignited hot-spot is able to propagate the fusion burn into the surrounding cold fuel. The only diagnostic that can measure the dynamics of thermonuclear burn is the nuclear fusion reaction history as a function of time. Distinct signatures in the α-curve of the reaction history have been found to be metrics of burn propagation, as well as robust ignition where the fuel mass is able to heat itself and the ice layer faster than the expansion rate decreases fusion rate. Recent advances in the Gamma Reaction History diagnostic (GRH) at the NIF have enabled measurements of the reaction history with 7 ps temporal resolution which is adequate to capture the signatures of burn propagation in the NIF. Measurements of the α-curve of ignited NIF experiments have shown signatures consistent with an ablative burn propagation model and are in agreement with xRAGE simulations. Recent high-gain implosions have shown the signatures of robust ignition predicted by analytic theory and simulations.

*This work was performed under the auspices of the U.S. Department of Energy by Los Alamos National Lab under Contract No. 89233218CNA000001This publication was prepared as an account of work conducted by the Laboratory for Laser Energetics and their sponsors. Neither the sponsors nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the sponsors or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the sponsors or any agency thereof.

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Presenters

  • Robert H Dwyer

    • University of Rochester

Authors

  • Robert H Dwyer

    • University of Rochester

  • Kevin D Meaney

    • Los Alamos National Laboratory (LANL)

  • Brian Michael Haines

    • Los Alamos National Laboratory
    • Los Alamos National Laboratory (LANL)

  • Hermann Geppert-Kleinrath

    • Los Alamos National Laboratory (LANL)

  • Jorge A Carrera

    • Lawrence Livermore National Laboratory

  • Eddie F Mariscal

    • Lawrence Livermore Natl Lab

  • William S Daughton

    • Los Alamos National Laboratory (LANL)
    • Los Alamos National Laboratory

  • Brian James Albright

    • Los Alamos National Laboratory (LANL)

  • Joshua Paul Sauppe

    • Los Alamos National Laboratory (LANL)

  • Chad J Forrest

    • University of Rochester
    • Laboratory for Laser Energetics (LLE)

  • Sean P Regan

    • University of Rochester

  • Yongho Kim

    • Los Alamos National Laboratory (LANL)